added method

README.md

@@ -1,40 +1,46 @@
 # Apache Exporter for Prometheus
 Exports server statistics provided by mod_status of an Apache HTTP server to Prometheus metrics format
 
+## Usage 
+
 It can be built with:
 
 ```
 mvn clean install
 ```
 
-## Usage 
-
 It can be importer in your Maven project with
 
 ```
 <dependency>
   <groupId>com.github.postfinance.prometheus</groupId>
   <artifactId>apache-exporter</artifactId>
-  <version>1.0.0</version>
+  <version>VERSION</version>
 </dependency>
 
 ```
 
+### ModStatus URL
+
 The Apache ModStatus URL where the metrics are read, can be configured with
 
+* A parameter in the ApacheExporter constructor
 * A System Property: httpdModStatusUrl
 * An Environment Property: HTTPD_MOD_STATUS_URL
 
 The default value is http://localhost/server-status?auto
 
-To obtain the metrics, use the method:
+### Apache HTTPD Metrics
+
+To obtain the metrics for apache, an istance of the ApacheExporter class should be created 
+and one of the following methods called:
 
+* First method
 
 ```
 public String export() throws IOException
 ```
-
-It returns a String in the format:
+returns a String in the format:
 
 ```
 # HELP apache_exporter_build_info A metric with a constant '1' value labeled by version, revision, branch, and goversion from which apache_exporter was built.
@@ -68,3 +74,11 @@ apache_workers{state="busy"} 2
 apache_workers{state="idle"} 6
 
 ```
+
+* Second method
+
+```
+public ArrayList<Collector.MetricFamilySamples> exportSamplesList()
+```
+
+It returns a list of samples of type Collector.MetricFamilySamples

src/main/java/ch/postfinance/prometheus/ApacheExporter.java

@@ -1,5 +1,6 @@
 package ch.postfinance.prometheus;
 
+import io.prometheus.client.Collector;
 import io.prometheus.client.CollectorRegistry;
 import io.prometheus.client.Counter;
 import io.prometheus.client.Gauge;
@@ -14,6 +15,8 @@
 import java.net.http.HttpResponse;
 import java.time.Duration;
 import java.time.Instant;
+import java.util.ArrayList;
+import java.util.Collections;
 
 public class ApacheExporter {
 
@@ -107,6 +110,19 @@ public String export() throws IOException {
         return new String(stream.toByteArray());
     }
 
+    public ArrayList<Collector.MetricFamilySamples> exportSamplesList() {
+        try {
+            mapStatusToMetrics(readApacheStatus());
+            serverUpGauge.set(1);
+        } catch (InterruptedException | IOException e) {
+            scrapeErrorsTotal.inc();
+            serverUpGauge.set(0);
+        }
+
+        return Collections.list(registry.metricFamilySamples());
+
+    }
+
     private void mapStatusToMetrics(String statusData) {
         statusData.lines().parallel().forEach(line -> {
             String[] elems = line.split(":");

src/test/java/ch/postfinance/prometheus/ApacheExporterTest.java

@@ -1,8 +1,10 @@
 package ch.postfinance.prometheus;
 
+import io.prometheus.client.Collector;
 import org.junit.Test;
 
 import java.io.IOException;
+import java.util.List;
 
 import static org.junit.Assert.*;
 
@@ -21,20 +23,46 @@ public void export() {
         }
     }
 
+    @Test
+    public void exportList() {
+        ApacheExporter exporter = new ApacheExporter("http://fakehost/status");
+
+        List<Collector.MetricFamilySamples> mfsList;
+
+        try {
+            for (int i = 0; i < 5; i++) {
+                mfsList = exporter.exportSamplesList();
+
+                for(Collector.MetricFamilySamples element : mfsList) {
+                    if(element.name.equals("apache_scrape_errors_total")){
+                        for(Collector.MetricFamilySamples.Sample sample : element.samples){
+                            assertEquals(i+1, (int)sample.value);
+                        }
+                    }
+
+                }
+
+                Thread.sleep(1000);
+            }
+        } catch (InterruptedException e) {
+            fail(e.getMessage());
+        }
+    }
+
     @Test
     public void testProperty(){
 
         ApacheExporter exporter = new ApacheExporter();
 
-        assertEquals(exporter.getStatusUrl(), "http://localhost/server-status?auto");
+        assertEquals( "http://localhost/server-status?auto", exporter.getStatusUrl());
 
         System.setProperty("httpdModStatusUrl", "http://e1-xxx-alsu001/server-status?auto");
 
-        assertEquals(exporter.getStatusUrl(), "http://e1-xxx-alsu001/server-status?auto");
+        assertEquals("http://e1-xxx-alsu001/server-status?auto", exporter.getStatusUrl());
 
         exporter = new ApacheExporter("http://host:port/midw-status");
 
-        assertEquals(exporter.getStatusUrl(), "http://host:port/midw-status");
+        assertEquals( "http://host:port/midw-status", exporter.getStatusUrl());
 
 
     }